Behind-the-ear hearing aids in which a sound tube conducts sound generated by the receiver of the hearing aid into the ear canal are well known in the art. In order to position the sound tube securely and comfortably in the ear canal, an earpiece is provided for insertion into the ear canal of the user. Typically, the earpiece is individually adapted to the human anatomy of the ear of the user.
A conventional earpiece which secures the end of the flexible hearing aid tube within the ear canal has to be Individually custom manufactured to fit the user's ear to sufficiently secure the hearing aid tube In place In the ear canal and prevent the earpiece from falling out of the ear and avoid acoustical feed backs, e.g., when the user is moving around. The custom made earpiece adds to the cost of the device and the time needed to fit the hearing aid.
U.S. Pat. No. 3,935,401 discloses an earpiece for an acoustic headset. The acoustic headset has sound transmitting tubes fitted with earpieces designed to engage the wearer's outer ear. The earpieces have a central hub that receives the acoustic tube, and a flange projecting symmetrically from the hub and intended to seal against the outer ear in the region of the ear canal. The flange becomes deformed as the wearer adjusts the centre of the earpiece into position communicating effectively with the ear canal. By using thinned regions, or sloping webs amounting to corrugations, or slots, or combinations of these, one region of the flange Is encouraged to wrinkle or to shrink so as to allow the central passage of the earpiece to be moved opposite a wearer's ear canal and yet the remainder of the flange can stand out and become conformed reasonably to the wearer's outer ear, acting with reasonable effectiveness to exclude ambient sounds.